Over-expression of p53 and c-erbB-2 oncoproteins in laryngeal carcinoma

An immunohistochemical analysis of over-expression of p53 and c-erbB-2 prot eins was performed on 27 biopsies of laryngeal carcinoma. The aim of this s tudy was to investigate whether there is a correlation between over-express ion of these proteins and the clinicopathological features of the tumor and to reveal any possible prognostic value. Paraffin sections of laryngeal ca rcinoma were studied using immunohistochemical staining with mouse and rabb it monoclonal antibodies, respectively, for p53 and c-erbB-2 proteins. The positive controls were paraffin-embedded specimens from ten breast carcinom as previously shown to express these proteins. Ten benign laryngeal nodules were immunohistochernically stained as negative controls. Samples from 74% of 27 patients with laryngeal carcinomas demonstrated positive nuclear and cytoplasmic (or membranous) staining for p53 protein and 48% were positive for c-erbB-2 protein. In the present study, while there was a slight diffe rence in the frequency of p53 over-expression among stage I-II and stage II I-IV tumors, there was no difference in the frequency of p53 over-expressio n among primary and recurrent tumors. There was no statistically significan t correlation between over-expression of the p53 and c-erbB-2 proteins and the age of the patients, tumor site, tumor grade, clinical stage, histopath ological grading of the tumor, alcohol consumption, and clinical outcome. T here was a statistically significant correlation between immunostaining of p53 and c-erbB-2 proteins (P = 0.037). While it was found that over-express ion of p53 was significantly associated with the presence of lymph node met astasis (P = 0.006), there was no association between the expression of c-e rbB-2 and lymph node status. The data demonstrated increased expression of p53 and c-erbB-2 proteins, presumed to be mutant, in laryngeal carcinomas. Hence, we conclude that p53 and c-erbB-2 over-expression as detected by imm unohistochemical staining in larynx carcinomas is not predictive of poor su rvival or disease-free survival.